The present invention refers to a coupling assembly for a machining device, e.g. a machine tool, such as an electro erosive machine tool, for mounting a work piece to be machined in a torsionally fixed manner. Thereby, the machining device is provided with a pallet support member, and the work piece is disposed on a pallet. The pallet has to be exactly positioned in the X-, Y- and Z-directions and, thereafter, has to be fixed to the pallet support member in an exactly centered position.
It is understood that exceptionally high demands are made not only as far as the exact positioning in the horizontal and vertical planes as well as the exact keeping of a central position are concerned, but it must also be ensured that the work piece can be clamped repeatedly in a well defined position, in the case that, if appropriate, several machining or measuring operations have to be performed on the same work piece.
In order to ensure a precise machining of the work piece, it is of paramount importance to withstand the loads occurring during machining, e.g. high rinsing pressures, by means of a rigid fixation.
Due to the fact that a measurement accuracy in the region of thousands of a millimeter has to be observed in connection with such coupling assemblies, the repositioning of work pieces is extremely time consuming and expensive.